Cylinder lock



Few w, new 31,484,473;

Y J. CRONING EYLINDER LOCK Filed Jan. 11, 1925 Patented rel-3.1a, 1924.

FOHANNES GRONING, (2F HAh-IBURG, GERIlZAIilY.

CYLINDER LOCK.

Application filed January 11, 1923.

To all whom it may concern:

Be it known that l, JorrANNns CRoNINo, a citizen of the Republic of Germany, residing at Hamburg, Germany, have invented certain new and useful Improvements in Cylinder Locks; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to letters or figures of reference marked thereon, which form a part of this specification.

The present invention relates to improvements in cylinder locks of the pin tumbler type, and more particularly refers to the cylinder plug of such looks.

The object of this invention is to provide improved means for reliably protecting the cylinder plug from axial displacement in said cylinder.

With this end in view the invention consists in certain novel features of construction and combinations of parts as will be hereinafter fully described and pointed out in the claims with reference to the accompanying sheet of drawings in which:

Figure 1 is a vertical longitudinal section of the cylinder lock showing the cylinder in section and the plug inserted therein in elevation; Fig. 2 is a plan in section of Fig. 1 and Fig. 3 is an end view of the rear face of the plug; Fig. 4 is an end view of the annular stop plate for securing the plug within the cylinder against axial displacement; Figs. 5 and 6 are views analogous to Fig. 3 illustrating the mode of applying the said stop plate to the plug; and Fig. 7 is a fragmentary vertical longitudinal section of Fig. 6. p

Similar letters of reference designate like parts throughout the several figures.

The plug a rotatably mounted within the stationary cylinder 5 rests or bears with a collar or flange 0 against a suitable shoulder of the front end of the said cylinder. The annular plate (Z suitably fixed in a circumferential groove 6 of the plug a bears against a corresponding shoulder of the inner or rear end of the cylinder. The flange 0 and the annular plate d actually form stops which hold the plug in the cylinder 6 in such a manner that the said plug may be rotated therein but-can not move in longitudinal direction. The plug is provided in Serial .l'l'o. 12,062.

its outer circumferential wall with two oppositely situated recesses f and 9 serving for the transmission of the rotation of the plug to the locking mechanism. Furthermore the plug has on its top a dovetailed groove it in which is located a bolt or bar 2' forming a support for the locking springs not shown. A fourth groove Z5 provided in the plug forms the key slot. The circularv groove c of the plug is interrupted or crossed by the said four longitudinal recesses or grooves (Fig. 8). The annular stop plate 03 l) the his I e diameter of which is equal to the outsi re diameter of the plug, has four inner projections or shoulders f g h and directed toward the centre of the annular stop plate 03 that fit into the corresponding recesses and grooves of the plug, (Fig. 5). Preferably at diametrically opposite places there are fastened to the outside circumference of the annular plate d rectangular lugs Z and m (Fig. 7 which serve for applying an implement when inserting the said plate. After the plate d has been placed upon the plug a to register with the groove 0 (Fig. 5), the said plate d is turned in the direction of the arrows until the lug m registers with the groove h (Fig. 6). In this position the projections f 9 h and 70 have engaged in the manner of a bayonet-coupling the corresponding full parts of the rear face of the plug a. If now the lug m is bent down from the position shown in dotted lines into the position shown in full lines (Fig. 7), so as to engage the rear part of the groove h, the said plate (Z on the one hand is secured against rotation on the plug and on the other hand prevents the bar 2' from axial displacement in its groove 7t.

In cylinder locks of well known construction the plug is secured against axial displacement by means of a separate disk or plate screwed onto the rear end face of the cylinder. This construction has the disadvantage that shocks and the like imparted to the lock may loosen the fixing screws of the said disk whereby the reliable function of the lock may be risked. This disadvantage is obviated by the present invention according to which the plug is secured in place and prevented from getting loose and from being axially displaced by means of the improved annular stop plate fastened upon the rear end of the plug in the manner of a bayonet coupling and adapted to rest or bear against the rear end of the cylinder. Besides this advantage the use of the improved bayonet coupling for rotatably connecting the plug to the cylinder will simplify and cheapen the whole construction of the lock. The annular groove in the plug can easily be made by means of the turning-lathe, the separate fixing screws are thus dispensed with also the drilling and countersinking of the screw holes as well as the cutting of the internal screw threads therein. This is a very important feature, as tapping-drills break very easily wherefroin results, as known, a great waste of tool and material.

I claim:

1. A cylinder lock of the kind described having a stationary cylinder and a rotatable flanged plug held in position therein, an annular stop plate securing said plug against axial displacement and abayonet connection between the plate and plug.

2. A cylinder lock of the kind described having in combination a stationary hollow ferential groove and a plurality of longitudinal grooves thereon, the latter traversing the former, an annular-stop plate fitting on the plug, projections on the inner Wall of the said annular stop plate, the said projections being adapted to slide in the longitudinal grooves and to lit in the circumferential groove of the plug, andmeans for securing the annular stop plate in the circumferential groove.

'3. A cylinder lock of the kind described, having in combination astationary hollow cylinder, a rotatable flanged plug therein,

an annular stop plate, means on the plug and on the annular stop plate, adapted to form a bayonet coupling, and means adapted to secure the annular stop plate'againstrotation on the plug.

In testlmony that my invention, I have signedmy name.

JOHANNES onom ve.

I claim the foregoing as p 

